If I have subscribed to the RadCarouselPanel.SelectedIsTopItem event, should I not get notifications when that property changes to false?

In my case, when the user scrolls the mouse wheel over the control or hits the little left/right buttons at the bottom of the carousel, the selected item certainly moves off of the top.  But the event is never fired.  It is only fired when I left click on the item to make the control force it to the top.


To illustrate, here is how I find the panel and subscribe to the events

var panel = this.Carousel.FindChildByType<RadCarouselPanel>();
panel.IsAnimatingChanged += Panel_IsAnimatingChanged;
panel.SelectedIsTopItem += Panel_SelectedIsTopItem;

I then have debug log lines in the two handler functions to let me know when the events fire.

private void Panel_SelectedIsTopItem(object sender, RoutedEventArgs e)
{
    var panel = (RadCarouselPanel)sender;
    Log.Debug($"Panel SelectedIsTopItem changed to {panel.IsSelectedTopItem}");
}

private void Panel_IsAnimatingChanged(object sender, RoutedEventArgs e)
{
    var panel = (RadCarouselPanel)sender;
    Log.Debug($"Panel is animating changed to {panel.IsAnimating}");
}

When I bring up my display the selected item is at the top by default







Then I use the mouse wheel or the scroll buttons to move the panel items without changing the selected item.  Note that the blue "selected" rectangle still appears around #002 to the left even though it is not #003 that is topmost





But all I get in my log is IsAnimatingChanged events 

15:31:50.690 [  1] DEBUG - Panel_IsAnimatingChanged: Panel is animating changed to True
15:31:50.977 [  1] DEBUG - Panel_IsAnimatingChanged: Panel is animating changed to False

But now if I  left-click the new topmost item (#003), then it becomes selected




and I am notified that SelectedIsTopMost has changed, along with an event about IsAnimating changed even though no animation occurs in this instance

15:36:16.447 [  1] DEBUG - Panel_IsAnimatingChanged: Panel is animating changed to True
15:36:16.725 [  1] DEBUG - Panel_SelectedIsTopItem: Panel SelectedIsTopItem changed to True
15:36:16.730 [  1] DEBUG - Panel_IsAnimatingChanged: Panel is animating changed to False

In order for the event SelectedIsTopMost to be useful to me, I have to be notified about it when it becomes false.   Why am I not being told this?


For sake of completeness, here is my XAML

<tk:RadCarousel x:Name="Carousel"
    Padding="0" Margin="0"
    Grid.Row="1"
    ItemsSource="{Binding ScansView}"
    VerticalContentAlignment="Top"
    IsVisibleChanged="Carousel_OnIsVisibleChanged"
    HorizontalAlignment="{Binding HorizontalAlignment}" VerticalAlignment="{Binding VerticalAlignment}"
    >

I have the following XAML

<Window x:Class="WpfApp46.MainWindow"
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
        xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
        xmlns:local="clr-namespace:WpfApp46"
        xmlns:telerik="http://schemas.telerik.com/2008/xaml/presentation"
        mc:Ignorable="d"
        Title="MainWindow" Height="450" Width="1200"
        DataContext="{Binding RelativeSource={RelativeSource Self}}">
    <Grid>
        <telerik:RadGridView ItemsSource="{Binding Foos}" AutoGenerateColumns="False">
            <telerik:RadGridView.Columns>
                <telerik:GridViewDataColumn DataMemberBinding="{Binding Foo1}" MinWidth="100" />
                <telerik:GridViewDataColumn DataMemberBinding="{Binding Foo2}" MinWidth="100" />
                <telerik:GridViewDataColumn DataMemberBinding="{Binding Foo3}" Width="*" />
                <telerik:GridViewDataColumn DataMemberBinding="{Binding Foo4}" MinWidth="100" />
                <telerik:GridViewDataColumn DataMemberBinding="{Binding Foo5}" MinWidth="100" />
                <telerik:GridViewDataColumn DataMemberBinding="{Binding Foo6}" MinWidth="100" />
            </telerik:RadGridView.Columns>
        </telerik:RadGridView>
    </Grid>
</Window>

and the following code behind

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Data;
using System.Windows.Documents;
using System.Windows.Input;
using System.Windows.Media;
using System.Windows.Media.Imaging;
using System.Windows.Navigation;
using System.Windows.Shapes;

namespace WpfApp46
{
    /// <summary>
    /// Interaction logic for MainWindow.xaml
    /// </summary>
    public partial class MainWindow : Window
    {
        public List<Foo> Foos { get; set; }

        public MainWindow()
        {
            Foos = new List<Foo>()
            {
                new Foo() { Foo1 = "Foo 1", Foo2 = "Foo 2", Foo3 = "Foo 3", Foo4 = "Foo 4", Foo5 = "Foo 5", Foo6 = "Foo 6" },
                new Foo() { Foo1 = "Foo 1", Foo2 = "Foo 2", Foo3 = "Foo 3", Foo4 = "Foo 4", Foo5 = "Foo 5", Foo6 = "Foo 6" },
                new Foo() { Foo1 = "Foo 1", Foo2 = "Foo 2", Foo3 = "Foo 3", Foo4 = "Foo 4", Foo5 = "Foo 5", Foo6 = "Foo 6" },
                new Foo() { Foo1 = "Foo 1", Foo2 = "Foo 2", Foo3 = "Foo 3", Foo4 = "Foo 4", Foo5 = "Foo 5", Foo6 = "Foo 6" },
                new Foo() { Foo1 = "Foo 1", Foo2 = "Foo 2", Foo3 = "Foo 3", Foo4 = "Foo 4", Foo5 = "Foo 5", Foo6 = "Foo 6" },
                new Foo() { Foo1 = "Foo 1", Foo2 = "Foo 2", Foo3 = "Foo 3", Foo4 = "Foo 4", Foo5 = "Foo 5", Foo6 = "Foo 6" },
                new Foo() { Foo1 = "Foo 1", Foo2 = "Foo 2", Foo3 = "Foo 3", Foo4 = "Foo 4", Foo5 = "Foo 5", Foo6 = "Foo 6" },
                new Foo() { Foo1 = "Foo 1", Foo2 = "Foo 2", Foo3 = "Foo 3", Foo4 = "Foo 4", Foo5 = "Foo 5", Foo6 = "Foo 6" },
            };

            InitializeComponent();
        }
    }

    public class Foo
    {
        public string Foo1 { get; set; }
        public string Foo2 { get; set; }
        public string Foo3 { get; set; }
        public string Foo4 { get; set; }
        public string Foo5 { get; set; }
        public string Foo6 { get; set; }
    }
}

Hello.

I have the same situation as https://www.telerik.com/forums/virtual-page-count.
Since the database has over 100 million data, I don't want to bring all the data into memory.
When a user clicks on a specific page, I'm trying to get only the data in that range from the DBMS.

I also read about Unbound Mode (https://docs.telerik.com/devtools/wpf/controls/raddatapager/features/unbound-mode)
But this seems to use code-behind.
I don't want to write a code-behind because I use the MVVM pattern.
How can I do it?

The code below has been simplified.

1. DataView.xaml

<UserControl x:Class="MyProject.Views.MyDataView"
             xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
             xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
             xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006" 
             xmlns:d="http://schemas.microsoft.com/expression/blend/2008" 
             xmlns:local="clr-namespace:MyProject.Views"
             xmlns:telerik="http://schemas.telerik.com/2008/xaml/presentation"
             xmlns:behaviors="http://schemas.microsoft.com/xaml/behaviors"
             mc:Ignorable="d" 
             d:DesignHeight="550" d:DesignWidth="1920">
    <Grid>
        <Grid.RowDefinitions>
            <RowDefinition Height="26" />
            <RowDefinition Height="400"/>
            <RowDefinition Height="28" />
        </Grid.RowDefinitions>

        <Grid Grid.Row="0" HorizontalAlignment="Right">
            <StackPanel Orientation="Horizontal">
                <TextBlock Text="Page Size" Margin="2 8 12 2"  FontWeight="SemiBold"/>

                <telerik:RadComboBox 
                                 Height="22"
                                 Margin="0 0 10 0"
                                 FontFamily="Segoe UI"
                                 ClearSelectionButtonVisibility="Visible" 
                                 ClearSelectionButtonContent="Show all" 
                                 DisplayMemberPath="DisplaySize" 
                                 ItemsSource="{Binding MyDataPageSize}" 
                                 SelectedItem="{Binding SelectedMyDataPageSize}"
                                 AllowMultipleSelection="False"
                                 Command="{Binding RefreshMyDataCommand}"/>
            </StackPanel>
        </Grid>

        <telerik:RadGridView x:Name="MyDataGridView"
                             Grid.Row="1"
                             IsFilteringAllowed="False"
                             AutoGenerateColumns="False"
                             ShowGroupPanel="False"
                             CanUserFreezeColumns="False"
                             RowIndicatorVisibility="Collapsed"
                             SelectionMode="Extended"
                             TextBlock.TextAlignment="Center"
                             CanUserSortColumns="False"
                             IsReadOnly="True"
                             Margin="10 5 10 0"
                             ScrollMode="RealTime"
                             ItemsSource="{Binding DynamicGridViewItemSource}"
        </telerik:RadGridView>

        <telerik:RadDataPager Grid.Row="2"
				x:Name="MyDataPager"
                              Width="{Binding ElementName=MyDataGridView, Path=ActualWidth}"
							  PageSize="{Binding SelectedMyDataPageSize.Size}"
							  Source="{Binding Items, ElementName=MyDataGridView}"
							  ItemCount="{Binding TotalItemCount}"
                              BorderThickness="1,0,1,1"
							  DisplayMode="All"
                              AutoEllipsisMode="Both"
							  NumericButtonCount="10"
							  IsTotalItemCountFixed="False" >
            <behaviors:Interaction.Triggers>
                <behaviors:EventTrigger EventName="PageIndexChanged">
                    <behaviors:InvokeCommandAction Command="{Binding PageIndexChangedCommand}"
                                           CommandParameter="{Binding ElementName=MyDataPager, Path=PageIndex}" />

                </behaviors:EventTrigger>
            </behaviors:Interaction.Triggers>
        </telerik:RadDataPager>
    </Grid>
</UserControl>

2. DataViewModel.cs

namespace MyProject.ViewModels
{
    public class StageDTO
    {
        public string StartNumber { get; set; }
        public string EndNumber { get; set; }
    }

    public class MyDataViewModel : ViewModelBase
    {

// some code

        private int _totalItemCount;
        public int TotalItemCount
        {
            get
            {
                return _totalItemCount;
            }
            set
            {
                _totalItemCount = value;
                OnPropertyChanged(nameof(TotalItemCount));
            }
        }

        public MyDataViewModel(CyclerMode mode)
        {
            // do something
        }

        public void ShowMyDataOfSelectedStage(object parameter)
        {
           StageDTO dto = parameter as StageDTO;
 
            // do something

          // and i calculate TotalItemCount here
                TotalItemCount = Convert.ToInt32(dto.EndNumber) - Convert.ToInt32(dto.StartNumber);
           
        }
    }
}

There may have been a typo in the process of simplifying, but there is no problem when i actually run the program.

TotalItemCount = Convert.ToInt32(dto.EndNumber) - Convert.ToInt32(dto.StartNumber);

The data goes in correctly in the code above, but nothing changes.

I made the changes below, but it still doesn't work.

ItemCount="{Binding TotalItemCount, UpdateSourceTrigger=PropertyChanged}"

If I change it like below
ItemCount="{Binding TotalItemCount, Mode=TwoWay}"

I am getting an exception like below.
System.InvalidOperationException: 'Setting RadDataPager.ItemCount is allowed in Unbound Mode only.'

How do I get it to work like I want?

I have a RadMultiColumnComboBox with AutoCompleteMode="Search". If I type "asdf" into the combo box, close the dropdown without actually selecting an item, and then refresh the page I want to clear "asdf", but I cannot figure out how to clear this text. I have tried setting the selected Item to null, setting AutoCompleteProvider.SearchText to an empty string, and setting the selected index to -1. 

What am I doing wrong?

Hi,

I would like to create a docking layout with 4 controls spread over 2 rows as in the attached image. I achieved this result using compass, but I need to create the same layout by design.

Thank you

Luigi

Hi. I have some question.

An exception occurred while debugging the ExecutiveDashboard demo source code.

exception text : 
System.InvalidOperationException: 'An error occurred while processing this request.'
DataServiceTransportException: The request was aborted: Could not create SSL/TLS secure channel.
WebException: The request was aborted: Could not create SSL/TLS secure channel.



An error occurred while downloading and installing the ExecutiveDashboard demo app(setup.exe).

install.log : 
The following properties have been set:
Property: [AdminUser] = true {boolean}
Property: [InstallMode] = HomeSite {string}
Property: [NTProductType] = 1 {int}
Property: [ProcessorArchitecture] = AMD64 {string}
Property: [VersionNT] = 10.0.0 {version}
Running checks for package '.NET Desktop Runtime 6.0.1 (x64)', phase BuildList
Checking conditions before installer checks for command 'net6desktopruntime_x64\windowsdesktop-runtime-6.0.1-win-x64.exe'
Result of running operator 'ValueNotEqualTo' on property 'ProcessorArchitecture' and value 'AMD64': false
Result of checking conditions before installer checks for command 'net6desktopruntime_x64\windowsdesktop-runtime-6.0.1-win-x64.exe' is: No action
Running external check with command 'C:\Users\jmkim\AppData\Local\Temp\VSD29A9.tmp\net6desktopruntime_x64\NetCoreCheck.exe' and parameters 'Microsoft.WindowsDesktop.App 6.0.1'
Process exited with code 0
Setting value '0 {int}' for property 'NetCoreCheck'
The following properties have been set for package '.NET Desktop Runtime 6.0.1 (x64)':
Property: [NetCoreCheck] = 0 {int}
Running checks for command 'net6desktopruntime_x64\windowsdesktop-runtime-6.0.1-win-x64.exe'
Result of running operator 'ValueNotEqualTo' on property 'ProcessorArchitecture' and value 'AMD64': false
Result of running operator 'VersionLessThan' on property 'VersionNT' and value '6.1.0': false
Result of running operator 'ValueEqualTo' on property 'NetCoreCheck' and value '0': true
Result of checks for command 'net6desktopruntime_x64\windowsdesktop-runtime-6.0.1-win-x64.exe' is 'Bypass'
'.NET Desktop Runtime 6.0.1 (x64)' RunCheck result: No Install Needed
Launching Application.
URLDownloadToCacheFile failed with HRESULT '-2146697208'
Error: An error occurred trying to download 'http://demos.telerik.com/wpf/executivedashboard/ExecutiveDashboard.application'.

The same problem occurred with the SalesDashboard demo source code and app.

What caused the problem?

Hello!

I need to make a custom separate scrollbar for RadGridView.

Please tell me how can I know if some of the rows of the RadGridView are already out of area of ​​visibility and how can I find out what part of the rows is visible and position of the part of the rows?

Hi,

I was not able to find this answer on the forum. It looks like a simple thing to do but I was not able to understand it.

I have three RadTreeView with the following xaml options: (IsDragDropEnabled="True" AllowDrop="True" telerik:ScrollingSettingsBehavior.IsEnabled="False" IsDragTooltipEnabled="False") . All three Trees have 2 level of data of 2 different type of objects. 

The drop of an item might be allowed or not, depending on a combination on:

• the origin tree of the Drag (tree 1, 2 or 3)
• the type of object selected (level 1 or level 2)
• the target tree (tree 1,2 or 3)
• the drop position (inside, after, before)

As an example, the level 2 objects of tree 1 cannot be dropped on tree 3, while on tree 2 the can only be dropped inside the level 1, or before/after the level 2 (not inside level 2).

I implemented all the controls to allow this behaviour in the handler of "DragDropManager.AddDropHandler", in which when the drop is not allowed I simply have that the DropAction = DropAction.None and everything is working fine.

However what I would like to have is that when the drop is not supposed to be allowed, the drop preview should not be visible. by drop preview I mean the line in between items when the drop position is after/before or the highlight of the target item when the drop position is inside. Note that I still would like to keep the drag preview of the source item,  and that I disabled the dragtooltip as not of interest.

I considered using the handler "DragDropManager.AddDragInitializeHandler" to set the AllowDrop to false for all the correct items, however sometimes (like in the example above) I want to disable the drop only for certain drop positions, thus the item AllowDrop property cannot be set to false at the beginning of the drag. 

What I think I should do is to use the handler "DragDropManager.AddDragOverHandler", in which I check if the drop is feasible. If it is not, I somehow disable the drop preview, if it is allowed, i enable it once again. This is where I'm stuck.

Considering the variable var options = DragDropPayloadManager.GetDataFromObject(e.Data, TreeViewDragDropOptions.Key) as TreeViewDragDropOptions;

If after checking that the drop is not allowed I set options.DropTargetItem.AllowDrop = false, the visual result is exactly what I need. However, from that moment on the handler "DragDropManager.AddDragOverHandler" does not fire anymore on that Item, so I cannot set it again to true.

If instead I set options.DropTargetItem.IsDropAllowed = false; nothing happens.

I tried to play with the dragvisual property, setting as an example the  dragVisual.IsDropPossible = false, but it doesn't change the result (I guess that this property is only for the dragtooltip that I disabled)

Note that, if possible, I also do not want to override the drop position from the not allowed to the allowed one, like suggested in the documentation (https://docs.telerik.com/devtools/wpf/controls/radtreeview/how-to/drag-and-drop/enabled-drop-inside-only). 

Could you please suggest me how to proceed? Please let me know if you need more information.

Thanks in advance for your help.

Hello,

We have performance issues on a WPF application. We did some analysis using dotTrace (attached screenshot) where we saw that the method Telerik.Windows.Controls.GridView.GridViewVirtualizingPanel.MeasureOverride(Size) is causing quite some delay. 

Are there any ways to get this more up to speed ?

Thanks !